49 
of food previously prepared for them. By experiments 
Mr, Lugrin has ascertained that a basin 35 meters (114.8 
feet) long, and 3 meters (9.84 feet) broad, with an aver- 
age depth of water of 40 centimeters (1.3 feet); (2) may 
contain 20,000 young fish from eight to twelve months 
old, or 3,000 two-year old trout, having an average 
weight of 250 grams (3 or a little more than % pound). 
These 20,000 young fish or 3,000 trout, consume about 
10 kilograms (about 22 pounds) of small shrimps per 
day ; (3) or 300 kilograms (about 660 pounds) per month. 
It has been proved by experiment that a basin having 
the above-mentioned dimensions can produce 300 to 350 
kilograms (660 to 770 pounds) of shrimps, without at all 
interfering with the Daphnia, Nais, Limnea, insect lar- 
vee etc., which simultaneously develop in the same basin. 
Under these conditions food will never be lacking. It 
is sufficient to have two basins for each lot of fish, so as 
to transfer then each month from one basin to the other. 
The system employed at Gremaz is, therefore, exceed- 
ingly profitable from an industrial point of view. But 
it is specially destined to render excellent service in stock- 
ing rivers with fish. Doing away with all the difficulty 
as regards food, it makes it possible and even economical 
to keep young fish, intended for stocking rivers, for a 
certain time in the basin free from all danger. Those 
young fish, which, owing to the lack of suitable and suff- 
ciently cheap food, had to be set out in the rivers at a 
very early age, before they had had time to gain strength, 
may now be safely left in the basins till they have grown 
stronger. When several months old the young fish is 
already vigorous; it knows how to flee from danger ; it 
is, therefore, better able than younger fish to escape num- 
erous accidents and causes of destruction. Rivers, there- 
(2.) These are the dimensions adopted for the new basins of, the Gremaz estab- 
lishment, the projected enlargement of which contemplates the creation of 136 
such basins, 
(3.) Ten kilograms (22 pounds), dry measure, of small shrimps represents about 
7 litres (about 12 pints of liquid measure. 
